Blackboard-eraser.



710,873,327. PATBNTED Dmlo, 1907.

VM. W. PERKINS.

BLAGKBOARD ERASER.

APPLIoATIoN FILED PEB. 24, 190s.

- tapered or reduced in thickness, so as form as to UNITED STATES MARTIN W. PERKINS, OF BATTLE CREEK, MICHIGAN.

BLACKBOARD-ERASER.

Specification of Letters Patent.

Patented Dec. 10, 1907.

Application led February 24. 1903. Serial No. 144.692.

To all whom t may concern.'

Be it known that I, MARTIN W. PERKINS, a citizen of the United States, residing at the city of Battle Creek, in the county of Calhoun and State of Michigan, have invented certain new and useful Im rovements in a Blackboard-Eraser, of W ich the following is a specification.

This invention relates to erasers, and is particularly designed to provide an im roved device of this character for use in c eaning blackboards.

It is furthermore designed to arrange the device for convenience in manipulation, and to have the entire eraser flexible and free from rigid parts, so as to effectually obviate damage to the blackboard when cleaning the same.

Another object of the invention is to have the device in a form that is especially adapted for taking up chalk dust, and also in such fpresent a comparatively large cleaning sur ace and at the same time to 'effectually it the hand and thereby facilitate the manipulation thereof.

With these and other objects in view, the present invention consists in the combination and arrangement of parts as will be herein-l after more fully described, shown in the accompanying drawing and particularly pointed out in the appended claims.

In the drawing: Figure 1 is a perspective view of a bla/ck board eraser'embodying the features of the present invention. Fig. 2 is a bottom plan view thereof; and, Fig. 3 is 'a cross-sectional view of the eraser.

Like characters of reference designate corresponding parts in each and every figure of the drawing.

As hereinbefore indicated, it is an important object of the present invention to provide a comparatively large cleaning surface and at the same time to have the device in a form which is convenient for handling, and to carry out this object, a circular form has been selected, and the body of the eraser is composed of a single continuous length of felt or other suitable material l, which is tightly coiled upon itself to form a flat disk-shaped body, the outer end of the strip of felt being to preserve as far as possible the circular or disk shape of the body, and this reduced end por- .tion is secured to the adjacent peripheral edge portion of the body by means of stitches 2.

The top and bottom of the body are flat, and the top is provided with a back, designated by the reference character 3, and formed of some strong, durable and iiexible material, preferably leather, which is designed to hold being held thereto by glue or other adhesive material. This flexible back of the eraser is a very im ortant feature of the invention, as it holds t e coils of the felt strip together in close proximity and at the same time permits of some flexibility so as to permit of' the eraser accommodating itself to unevennesses in a blackboard, to permit of the chalk dust being taken up in the joints between the coils, and to obviate the usually. rigid part of an eraser, which is liable to injure the board when it is accidentally brought violently into contact therewith. In the absence of a wooden or other rigid back, the eraser may be manipulated with freedom and without any particular care, as there is no danger of .damaging the board with anypart of the eraser. v

To facilitate the handling of the eraser, there is provided a handle 4, in the form of a loop, formed by a fiexible strap, preferably of leather, with its ends passed inwardly through slits or incisions 5, inthe back and then inserted between the back and the coil of felt, where it is glued to the coil and the back. The intermediate portion of the strap is sufficiently loose as to permit of the fingers of the hand being thrust through the loopshaped handle and then grasped upon the peripheral edge of the body, whereby the eraser may be conveniently manipulated in cleaning a blackboard.

From vthe foregoing description, it is apparent that the device of the present invention is very simple, inexpensive and durable, and in view of its flexibility is particularly well ada ted to effectually take up chalk dust, andpin this particular it isa sanitary device. Furthermore, its flexibility prevents injury to the blackboard and renders its manipulation easier and more comfortable.

Although the eraser has been shown and described as circular in shape, it may be elliptical or of other shape, and therefore 1 do not the precise details as set forth, as changes in the form, proportion, size and minor details may be made, within the scope of the claims, without departing from the s irit or sacrificv .1 ing any of the advantages of t e invention.

the coils of the felt strip in place by wish to be understood as limiting myself to Having thus described the invention, what is claimed and desired to be secured by Letters Patent, is:

A Wholly flexible blackboard eraser, coniprising a spirally Wound 'flexible strip constituting a body having a iiat top and bottom7 the eXtreme outer end of the strip being secured to the outer edge of the body, and the coils of the spiral being otherwise disconnected, a back formed of freely flexible material covering the entire top of the body and closing the joints between the turns of the spiral to prevent dust Working through the eraser,

said back being secured to the individual coils', and said coils being freely separable from one another and capable of syn'eading te collect chalk dust, the back having spaced incisions, and a flexible strap handle passing through the incisions and secured between the body and the back.

In testimony whereof I have signed my naine to this specification in presence of' tw-o Witnesses.

MARTIN IV. PERKINS.

WVitnesses z DUANE C. SALIsBURY, Rosa Boo'rrr. 

